JP2002368663A - Adaptive antenna system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adaptive antenna system that varies antenna directivity, on the basis of the result of estimating direction and degree of angle spread, using an array antenna. SOLUTION: The adaptive antenna system employs a major wave direction estimate section 5, that uses an output signal 4 from a reception section 3 for estimating the arrival direction of an incoming wave with a maximum power, an angle spread estimate section 6 that estimates angle spread in the arrival direction of the incoming wave with the maximum power, and a weight- generating section 7 that directs the directivity of the array antenna 1 in the arrival direction of the incoming wave with the maximum power and generates a variable array weight, on the basis of a result of estimate by the angle spread estimate section 6 for the beam width, and can form directivity of the array antenna with an optimum beam width, according to the spread angle in a direction of a desired wave.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adaptive antenna device that changes an antenna directivity based on a result of estimating a direction and an angle spread using an array antenna.

[0002]

2. Description of the Related Art As a method of estimating a direction of arrival of a radio wave using an array antenna including a plurality of antenna elements,
There are MUSIC, ESPRIT, Capon and Fourier methods. For example, regarding the MUSIC method, reference R. O.
Schmidt, “Multiple Emitter
Location and Signal Para
meter Estimation ”, IEEE Tr
ans. , AP-34, pp. 276-280 (198
6).

As a method for estimating the angular spread of an incoming wave, N.I. S. M. Shah et al., "Simultaneous Estimation of Direction of Arrival and Angular Spread Using MUSIC Algorithm", IEICE Communications Society Conference B-1-31, 2000. Also, if the desired wave and the interference wave direction are known,
A DCMP method is generally known as a beam forming algorithm for directing a directional beam in a desired wave direction and nulling in an interference wave direction.

Further, Japanese Patent Application Laid-Open No. 2000-216620 discloses a method for adaptively changing the directivity of an antenna based on the result of estimating the direction of arrival of a radio wave. Hereinafter, FIG.
The operation will be described with reference to FIG. First, the plurality of receiving antennas 50-1 to 50-L and the high-frequency signals 51-1 to 51-L received by these receiving antennas are respectively 2
Using a signal distribution means 52 for distribution and a high-frequency signal of one of the systems distributed by the signal distribution means 52, a covariance matrix of reception signals received by the plurality of antennas 50-1 to 50-L is obtained and calculated. Azimuth measurement means 53 using the MUSIC method which outputs the covariance matrix and the azimuth information of the plurality of arriving waves based on the azimuth measurement of the plurality of arriving waves, and the measurement results obtained by the azimuth measurement means 53 Designated signal storage means 54 for storing one azimuth information designated by the azimuth information of the plurality of arriving waves, and receiving the high-frequency signal of the other system distributed by the signal distribution means 52, A weight calculation circuit 55 for calculating a weight for suppressing a signal other than the one specified azimuth stored based on the covariance matrix; Weighting means 56 for weighting the high-frequency signals 51-1 to 51-L received by the plurality of receiving antennas 50-1 to 50-L based on the weights calculated by the weighting calculation circuit 55, and output from the weighting means. And a signal synthesizing means 57 for synthesizing and outputting a high-frequency signal, and an output of the signal synthesizing means 57 is demodulated by a demodulation section 58.

[0005]

Conventionally, a directional beam is formed in the direction of arrival of an estimated desired wave. However, in an actual propagation environment, the influence of reflection and diffraction due to a building or the like in the vicinity of a radio station. In response, radio waves arrive with an angular spread. When directing a directional beam in the direction of the arrival of a desired wave, formation of an optimal directional beam according to the angular spread has not been considered in the past. Further, in an environment where a plurality of waves arrive, as a method of selecting an optimal incoming wave, it is general to select a maximum power wave. However,
Even if the received power is large, there is a possibility that a radio wave including many multipath waves may be selected.

[0006] The present invention uses the angle spread estimation result,
The beam width in directional beam forming is made variable. It is another object of the present invention to provide an adaptive antenna apparatus that selects an incoming wave direction having a small angular spread when a plurality of incoming waves exist and directs a directional beam in this direction to improve transmission / reception quality. Furthermore, for the interference wave direction,
An object of the present invention is to provide an adaptive antenna device that enables robust interference wave suppression even when an arrival direction estimation error is included by forming a null having a null width according to the angular spread of an interference wave.

[0007]

According to the present invention, a main wave direction estimating unit for estimating the arrival direction of an incoming wave having the maximum power using an output signal of a receiving unit, An angle spread estimating unit for estimating the angle spread in the direction of arrival, and directing the directivity of the array antenna in the direction of arrival of the arriving wave having the maximum power, and further, the beam width is based on the estimation result of the angle spread estimating unit. The directivity of the array antenna having the optimum beam width can be formed by the angular spread in the desired wave direction by the weight generation unit that generates the variable array weight.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 of the present invention is directed to an array antenna composed of a plurality of antenna elements, and a signal of an incoming wave received by each antenna element of the array antenna after frequency conversion. A receiver for performing quadrature detection,
A main wave direction estimating unit for estimating the arrival direction of the incoming wave having the maximum power using the output signal of the receiving unit, and the arrival direction of the incoming wave having the maximum power using the output of the main wave direction estimating unit. An angle spread estimating unit for estimating an angle spread, and an array for directing the directivity of the array antenna in an arrival direction of the arriving wave having the maximum power, and further changing a beam width based on the estimation result of the angle spread estimating unit. An adaptive signal processing unit comprising: a weight generating unit configured to generate a weight; a receiving beam forming unit configured to multiply and combine an output signal of the receiving unit with the array weight; and a demodulating unit performing demodulation processing on an output signal of the receiving beam forming unit. An antenna device, wherein the beam width of the main lobe can be varied according to the angular spread with respect to the main wave direction, and when the angular spread is larger than a predetermined value, From the main wave direction, including the multi-path,
There is an effect that the multipath suppression effect can be further enhanced by directing the directivity of the narrow beam.

According to a second aspect of the present invention, there is provided an array antenna including a plurality of antenna elements, and a receiving apparatus for performing quadrature detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna. Unit, an arrival direction estimating unit for estimating the directions of arrival and their power of a plurality of incoming waves using output signals of the receiving unit, and a maximum power from the plurality of incoming waves using the output of the direction of arrival estimating unit. An angle spread estimating unit for selecting a wave, estimating an angle spread for an incoming wave whose power is within a predetermined value with respect to the maximum power wave among the plurality of incoming waves, and an incoming wave power for the maximum power wave. When there is an incoming wave within a predetermined value, an array weight for directing the directivity of the array antenna is generated in the direction in which the angular spread is minimized, and in the absence of the incoming wave, in the direction of the maximum power wave. An adaptive antenna apparatus having a weight generation unit, a reception beam forming unit configured to multiply and combine an output signal of the reception unit with the array weight, and a demodulation unit performing demodulation processing on an output signal of the reception beam forming unit. It is possible to direct the main beam in the direction of arrival of the arriving wave with the smallest angular spread, and to select the arriving wave that is relatively good in terms of received power and that has small delay dispersion between rays constituting the angular spread. This has the effect of improving reception quality by increasing the multipath suppression effect.

According to a third aspect of the present invention, there is provided an array antenna composed of a plurality of antenna elements, and a receiving apparatus for performing quadrature detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna. Unit, a main wave direction estimating unit for estimating the arrival direction of the incoming wave having the maximum power using the output signal of the receiving unit, and the arrival wave having the maximum power using the output of the main wave direction estimating unit. An angle spread estimating unit for estimating an angle spread in a direction of arrival, a weight generating unit for generating an array weight for directing the directivity of the array antenna in the direction of arrival of the arriving wave having the maximum power, and the array weight for a transmission signal. A transmission beam forming unit that multiplies the transmission beam forming unit, and a transmitting unit that transmits the output of the transmission beam forming unit from the array antenna, The main lobe can be transmitted in a directional pattern in which the beam width of the main lobe is varied according to the angular spread of the incoming wave, and it has the effect of sufficiently reducing interference with radio stations other than the radio station that is to communicate. Have.

According to a fourth aspect of the present invention, there is provided an array antenna comprising a plurality of antenna elements, and a receiving apparatus for performing orthogonal detection after frequency conversion of a signal of an incoming wave received by each antenna element of the array antenna. Unit, an arrival direction estimating unit for estimating the arrival directions and their powers of a plurality of incoming waves using output signals of the receiving unit, and a maximum power from the plurality of arrival directions using the output of the arrival direction estimating unit. An angle spread estimating unit for selecting a wave, estimating an angle spread for an incoming wave whose power is within a predetermined value with respect to the maximum power wave among the plurality of incoming waves, and an incoming wave power for the maximum power wave. When there is an incoming wave within a predetermined value, a weight for generating an array weight for directing the directivity of the array antenna in the direction in which the angular spread is minimized, and in the absence of the incoming wave, in the direction of the maximum power wave. A transmission beam forming unit that multiplies a transmission signal by the array weight, and a transmitting unit that transmits an output of the transmission beam forming unit from the array antenna. Interference with radio stations other than the desired radio station can be sufficiently reduced, and when there are a plurality of arriving waves, the received power is relatively good and the elements forming the angular spread It is possible to select an arrival direction in which delay dispersion between waves is small and to transmit in that direction, thereby having an effect that the reception quality at a desired wireless station can be improved.

According to a fifth aspect of the present invention, there is provided the adaptive antenna apparatus according to the second or fourth aspect, wherein the beam width of the directivity formed by the weight generator is varied based on the estimation result of the angle spread estimator. Yes, it is possible to transmit with a directivity pattern in which the beam width of the main lobe is varied according to the angular spread of the arriving wave, and it is possible to sufficiently reduce interference with radio stations other than the radio station to be communicated with Has an action.

According to a sixth aspect of the present invention, when the angular spread is larger than a predetermined value, the weight generator forms a directional beam having a reduced beam width.
The adaptive antenna device described above has an operation of transmitting and receiving a directivity pattern in which a beam width of a main lobe is varied according to an angular spread of an incoming wave.

According to a seventh aspect of the present invention, there is provided an array antenna including a plurality of antenna elements, and a receiving apparatus for performing quadrature detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna. Unit, a main wave direction estimating unit for estimating a direction of arrival of an incoming wave having a maximum power using an output signal of the receiving unit, and an interference wave for estimating an arrival direction of an interference wave using an output signal of the receiving unit. Arrival direction estimating unit, an interference wave angle spread estimating unit for estimating the angular spread of the direction of arrival of the interference wave using the output of the interference wave arrival direction estimating unit, and the arrival direction of the arriving wave having the maximum power, If the direction of the arriving wave having the maximum power is not the same as the direction of arrival of the interference wave, the directivity of the array antenna is changed so that the direction of arrival of the interference wave has a width corresponding to the angular spread of the interference wave. A weight generation unit for generating an array weight for forming a signal; a reception beam formation unit for multiplying and combining the output signal of the reception unit with the array weight; and a demodulation unit for performing demodulation processing on an output signal of the reception beam formation unit. And an adaptive antenna device having a null width in accordance with the angular spread of the interference wave, and a high directivity having a high effect of suppressing the interference wave is formed even when an error is included in the arrival direction estimation. This has the effect of improving the reception quality.

According to an eighth aspect of the present invention, there is provided an array antenna comprising a plurality of antenna elements, and a receiving apparatus for performing orthogonal detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna. Unit, an arrival direction estimating unit for estimating the directions of arrival and their power of a plurality of incoming waves using output signals of the receiving unit, and a maximum power from the plurality of incoming waves using the output of the direction of arrival estimating unit. Selecting a wave, among the plurality of arriving waves, an angle spread estimating unit that estimates an angle spread for an arriving wave whose power is within a predetermined value for the maximum power wave, and using an output signal of the receiving unit. An interference wave arrival direction estimating unit for estimating an arrival direction of the interference wave, an interference wave angle spread estimating unit for estimating an angle spread of the arrival direction of the interference wave using an output of the interference wave arrival direction estimation unit, and Electric power In the case where an incoming wave whose incoming wave power is within a predetermined value is present, the directivity of the array antenna is directed in the direction in which the angular spread is minimized, and in the absence of the incoming wave, in the direction of the maximum power wave. If the direction in which the directivity is directed and the arrival direction of the interference wave are not the same, weight generation for generating an array weight for forming a directivity null having a width corresponding to the interference wave angle spread in the arrival direction of the interference wave An adaptive antenna apparatus having a unit, a receiving beam forming unit configured to multiply and combine an output signal of the receiving unit with the array weight, and a demodulating unit performing demodulation processing on an output signal of the receiving beam forming unit. A null width corresponding to the angular spread of the wave can be formed, and even when the direction of arrival estimation contains an error, the directivity with a high effect of suppressing the interference wave is formed. Improvement has the effect of it is.

According to a ninth aspect of the present invention, there is provided an array antenna including a plurality of antenna elements, and a receiving apparatus for performing quadrature detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna. A main wave direction estimating unit for estimating an arrival direction of an incoming wave having a maximum power using an output signal of the receiving unit; and an interfering wave arrival estimating an interfering wave arrival direction using the output signal of the receiving unit. A direction estimating unit, an interference wave angle spread estimating unit that estimates an angular spread of the interference wave arrival direction using an output of the interference wave arrival direction estimating unit, and the array antenna is arranged in a direction of arrival of the arriving wave having the maximum power. If the direction of the arriving wave having the maximum power and the direction of arrival of the interference wave are not the same, the direction of arrival of the interference wave has a directional null having a width corresponding to the interference wave angle spread. An adaptive antenna apparatus comprising: a weight generation unit that generates an array weight to be formed; a transmission beam formation unit that multiplies a transmission signal by the array weight; and a transmission unit that transmits an output of the transmission beam formation unit from the array antenna. Therefore, it is possible to form a null width according to the angular spread of the interference wave, and even when an error is included in the arrival direction estimation, a high directivity having a high effect of suppressing the interference wave is formed. It has the effect of improving communication quality.

According to a tenth aspect of the present invention, there is provided an array antenna comprising a plurality of antenna elements, and a receiving apparatus for performing orthogonal detection after frequency conversion of a signal of an incoming wave received by each antenna element of the array antenna. Unit, an arrival direction estimating unit for estimating the directions of arrival and their power of a plurality of incoming waves using output signals of the receiving unit, and a maximum power from the plurality of incoming waves using the output of the direction of arrival estimating unit. Selecting a wave, among the plurality of arriving waves, an angle spread estimating unit that estimates an angle spread for an arriving wave whose power is within a predetermined value for the maximum power wave, and using an output signal of the receiving unit. Interference wave arrival direction estimating unit for estimating the arrival direction of the interference wave,
An interference wave angle spread estimating unit for estimating an angular spread of the direction of arrival of the interference wave using an output of the interference wave arrival direction estimating unit; and an incoming wave whose incoming wave power is within a predetermined value with respect to the maximum power wave. Direction, the direction of the array antenna is directed to the direction in which the angular spread is minimized, and if not present, to the direction of the maximum power wave, the direction in which the direction of the array antenna is directed, and the direction of arrival of the interference wave. Are not the same, a weight generation unit that generates an array weight that forms a directional null having a width corresponding to the interference wave angle spread in the arrival direction of the interference wave, and a transmission that multiplies a transmission signal by the array weight An adaptive antenna device having a beam forming unit and a transmitting unit for transmitting an output of the transmitting beam forming unit from the array antenna, wherein the adaptive antenna device has a null width corresponding to an angular spread of an interference wave. It is possible to, even if it contains errors in the arrival direction estimation, by high directivity of suppression of the interference wave is formed, it has an action that can improve the communication quality at the time of transmission.

According to the eleventh aspect of the present invention, the arrival direction estimation algorithm in the main wave direction estimator is switched according to the magnitude of the angular spread of the arrival wave.
Or the adaptive antenna device according to 6, which has an effect of selecting an optimal direction of arrival estimation in accordance with the angular spread and improving the estimation accuracy.

According to a twelfth aspect of the present invention, the arrival direction estimation algorithm in the arrival direction estimation unit is switched according to the magnitude of the angular spread of the arrival wave.
The adaptive antenna device described in 4, 5, 8, or 10, which has an effect of selecting an optimal direction of arrival estimation in accordance with an angle spread and improving an estimation accuracy.

According to a thirteenth aspect of the present invention, the adaptive antenna according to any one of the seventh to tenth aspects, switches an arrival direction estimation algorithm in the interference wave arrival direction estimating unit according to the magnitude of the angular spread of the interference wave. This device is capable of selecting an optimal direction-of-arrival estimation in accordance with the angle spread, and has an effect of improving estimation accuracy.

According to a fourteenth aspect of the present invention, when the angular spread is larger than a predetermined value, the direction of arrival estimation algorithm is switched to an algorithm to which spatial smoothing processing is added. Adaptive antenna device, which has an effect of enabling selection of an optimal direction-of-arrival estimation in accordance with the angle spread and improving the estimation accuracy.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram showing a configuration of an adaptive antenna apparatus. The operation will be described below with reference to FIG. M array antennas 1 (however, M
> 1).
High frequency signal 2 received by each of antenna elements 1-1 to 1-M
-1 to 2-M are orthogonally demodulated after being frequency-converted in the receiving units 3-1 to 3-M connected to the antenna elements 1-1 to 1-M, and received by orthogonal I and Q signals. The signals are converted into signals 4-1 to 4-M. Each received signal 4-1 to 4
−M is divided into two, one is input to the main wave direction estimating unit 5 and the other is input to the receiving beam forming unit 8.

The main wave direction estimating unit 5 estimates the arrival direction of an incoming wave having the maximum power. Hereinafter, the operation will be described.
Hereinafter, a complex digital signal expressed as a real part and a Q signal as an imaginary part is represented as a received signal x (k) using a signal sampled for each of the I signal and the Q signal. First, the received signal x _{1 at the} sample time kΔT (where k is a natural number and ΔT is a sampling interval) obtained from the received signals 4-1 to 4-M, respectively.
(K), x ₂ (k),. . . , X _M (k) to form a reception vector x (k) represented by (Equation 1), and further, using the reception vectors x (k) accumulated every predetermined N sample periods, a correlation matrix of (Equation 2) Find R. In this case, the correlation matrix R is an (M × M) matrix.

[0025]

(Equation 1)

[0026]

(Equation 2)

Next, the arrival angle is evaluated for each predetermined angle step Δθ using the arrival angle evaluation function based on the Capon method. The arrival angle evaluation function is described in J. Literature. Capon, “Hig
h-Resolution Frequency-Wa
Vendor Spectrum Analysis
s. "Proc. IEEE, 57 (8), pp. 140.
8-1418, 1969, and is represented by (Equation 3).

[0028]

(Equation 3)

Where a (θ) represents the complex response of the array antenna to the azimuth θ. (Hereinafter, referred to as array mode vector) Further, R ^-1 is the inverse matrix of R.

In the angle spectrum of the result of the angle of arrival evaluation
Yields several maxima, of which the largest
Is the maximum power wave, and the angle that gives the maximum peak is the main wave.
Direction θ ₀And

Next, the operation of the angle spread estimating section 6 will be described below.

The main wave direction θ obtained from the main wave direction estimating unit 5
_The angle spread parameter δ is evaluated at predetermined angle steps Δδ using the angle spread evaluation function shown in (Equation 4).

[0033]

(Equation 4)

Here, a _x (θ) is a generalized array mode vector extended to take an argument in the complex domain with respect to the array mode vector a (θ). To the angular spread spectrum obtained by varying the angular spread parameter [delta] in equation (4), the estimated value of the angular spread value [delta] ₀ giving the maximum peak.

Here, the angle spread is estimated using the generalized array mode vector with respect to the Capon method, but the angle spread estimation is performed by applying the generalized array mode vector similarly to the MUSIC method and the ESPRIT method. Is the same.

The weight generator 7 calculates the estimated main wave direction value θ _0.
Then, using the estimated angular spread value δ ₀ , an array weight having directivity corresponding to the main beam direction θ ₀ and the beam width corresponding to δ ₀ is generated. Hereinafter, an operation in the case of using the Dorf-Chebyshev directivity synthesis method will be described. The Dorf-Chebyshev directivity synthesis method determines the excitation distribution such that the directivity of the antenna matches the Chebyshev polynomial, so that the side lobe suppression value S for the main lobe is determined.
LL can be set arbitrarily, and by reducing the side lobe suppression value SLL, the beam width of the main lobe is reduced. For details, see, for example, L. Stuzman et al. "Antenna Th
eory and Design ", Wiley, 19
81 pp. 537-542. Here, an outline of the case where an eight-element linear array antenna is used is shown below. In the case of eight elements (M = 8), the array weight in which the main lobe direction is θ ₀ and the side lobe suppression value SLL is represented by (Equation 5).

[0037]

(Equation 5)

[0038] Here, s _m below from the equation (6) (Equation 1
0).

[0039]

(Equation 6)

[0040]

(Equation 7)

[0041]

(Equation 8)

[0042]

(Equation 9)

[0043]

(Equation 10)

Here, m = 1 to 8, λ is the wavelength of the carrier, and d is the distance between the array elements.

Here, when the angular spread is larger than the predetermined value A1, the weight generator 7 forms a directional beam having a reduced beam width. For example, A1 = 10 ° and δ ₀ ≦
If it is 10 °, SLL = 20 dB, and δ ₀ > 10 °
Then, by setting SLL = 10 dB, the weight generation unit 7 determines that the angular spread is larger than the predetermined value A1.
A directional beam with a reduced beam width can be formed.

The reception beam forming section 8 includes a weight generating section 7
Using the obtained array weights, the received signals are multiplied and combined. That is, a composite signal y (k) is output for the received signal x _m (k) as shown in (Equation 11). Here, * indicates a complex conjugate.

[0047]

[Equation 11]

The demodulation section 9 performs demodulation processing on the combined signal y (k) from the reception beam forming section 8 and outputs decoded data.

As described above, in the present embodiment, the beam width of the main lobe can be changed by the weight generator 7 in accordance with the angular spread with respect to the main wave direction. When the angular spread is large, the temporal variance between the rays constituting the angular spread is also large, so when the angular spread is larger than a predetermined value, from the main wave direction including those multipaths,
By directing the narrow beam directivity, the multipath suppression effect can be further enhanced, and the reception quality can be enhanced.

(Embodiment 2) FIG. 2 is a block diagram showing a configuration of an adaptive antenna apparatus. The operation will be described below with reference to FIG. M array antennas (where M>
It is composed of the antenna elements 1-1 to 1-M of 1). High-frequency signals received by the antenna elements 1-1 to 1-M 2-
The reception signals 1-2-M are orthogonally demodulated after being frequency-converted in the receiving units 3-1-3-1-M connected to the antenna elements 1-1-1-1-M, and are reception signals composed of orthogonal I and Q signals. It is converted to 4-1 to 4-M. Each received signal 4-1 to 4-
M is divided into two, one of which is input to the arrival direction estimation unit 10 and the other is input to the reception beam forming unit 8.

The direction-of-arrival estimating unit 10 estimates the directions of arrival of a plurality of arriving waves and their powers using the output signals of the receiving unit. The operation will be described below. In the following,
Using a signal sampled for each of the I signal and the Q signal, a complex digital signal represented by the I signal as a real part and the Q signal as an imaginary part is represented as a received signal x (k). First, received signals x ₁ (k), x at sample times kΔT (where k is a natural number and ΔT is a sampling interval) obtained from received signals 4-1 to M, respectively.
₂ (k),. . . , X _M (k) to form a reception vector x (k) represented by (Equation 1), and further, using the reception vectors x (k) accumulated every predetermined N sample periods, a correlation matrix of (Equation 2) Find R. In this case, the correlation matrix R is an (M × M) matrix. Next, the arrival angle is evaluated for each predetermined angle step Δθ using the arrival angle evaluation function based on the MUSIC method. The arrival angle evaluation function is represented by (Equation 12).

[0052]

(Equation 12)

Here, E _N is a noise space matrix, which is obtained as follows. When the number of arriving waves is S, the eigenvalues λ ₁ to λ _M obtained by eigenvalue decomposition of the correlation matrix R, when arranged in descending order, have the relationship of (Equation 13) and belong to the noise eigenvector space (MS). E _N = [e _{s + 1} ,... Using the eigen vector e _s of the correlation matrix R as a column vector. . . , E _M ] form the noise eigenspace matrix.

[0054]

(Equation 13)

Since the number of arriving waves S is generally unknown, the distribution of eigenvalues and the method described in the literature M.P. Wa
x and T. Keilath, “Detection
no of Signals by Informati
on Theoretic Criteria ", IE
EE Trans. On Acoustics, Spe
etch and Signal Processin
g, Vol. ASSP33 (2), pp. 387-39
2, a signal number determination criterion described in February (1985) is used for determination. Also, as a result of the angle of arrival evaluation, the obtained angle spectrum has several local maxima, but the maximum peak among them is the maximum power wave, and the angle giving the maximum peak is the main wave direction θ ₀ , search the remaining (S-1) pieces of peak direction in descending order, the respective direction of arrival and theta _n. Where n = 1, ...,
S-1. The received power for each direction of arrival is estimated using (Equation 14). Where n = 0, ...,
S−1, and I is an M × M unit matrix.

[0056]

[Equation 14]

The angle spread estimating unit 11 calculates a plurality of directions of arrival obtained by the direction-of-arrival estimating unit 10 and estimated power values thereof.
The maximum power wave and the arriving wave power for the maximum power wave have a predetermined value L
Estimate the angular spread for incoming waves in p. That is,
| Perform ≦ L _p satisfy theta _v for only (number 15) direction of arrival angle spread estimation using _{| P (θ n) -P (} θ 0). Here, n = 1,..., S−1.

[0058]

(Equation 15)

Here, a _x (θ) is a generalized array mode vector extended from the array mode vector to take an argument in the complex domain. With respect to the angle spread spectrum obtained by evaluating the angle spread parameter δ in (Equation 15) for each predetermined angle step Δδ, the angle spread value δ ₀ giving the maximum peak is set as the estimated angle spread value δv ₀ with respect to the arrival direction θv. .

Here, the direction of arrival estimation and the angle spread estimation are performed using the MUSIC method.
The estimation can be performed in the same manner by using the RIT method or the like.

When there are a plurality of arriving waves for which the angular spread is estimated, the weight generating section 12 generates an array weight for directing the array antenna main beam in a direction in which the angular spread is minimized. When the number of arriving waves whose angular spread is estimated is one, the main beam is directed in the direction of arrival. As the array weight wk, the Dorf-Chebyshev directivity synthesis method described in the first embodiment can be applied.

The reception beam forming unit 8 includes the weight generating unit 1
Using the array weight wk generated in step 2, the received signal is multiplied and synthesized. That is, for the received signal x _m (k) as shown in equation (11), to output combined signal y (k). Here, * indicates a complex conjugate.

The demodulation section 9 performs demodulation processing on the combined signal y (k) from the reception beam forming section 8 and outputs decoded data.

As described above, in the present embodiment, when the arrival direction estimating unit 10 and the angle spread estimating unit 11 include a plurality of arriving waves whose arriving wave power is within a predetermined value with respect to the maximum power wave, the Out of the waves, the main beam can be directed in the direction of arrival of the arriving wave having the smallest angular spread, the received power is relatively good, and the delay dispersion between the rays constituting the angular spread is small. Waves can be selectively received, and the reception quality can be improved by increasing the multipath suppression effect.

In the present embodiment, the width of the main beam with respect to the angular spread is not specifically described. However, as described in the first embodiment, the beam width can be varied according to the estimated angle spread. The configuration may be as follows. In this case, in addition to the effects described above, the effects described in the first embodiment are added.

(Embodiment 3) FIG. 3 is a block diagram showing a configuration of an adaptive antenna apparatus. The operation will be described below with reference to FIG. M array antennas (where M>
It is composed of the antenna elements 1-1 to 1-M of 1). High-frequency signals received by the antenna elements 1-1 to 1-M 2-
The reception signals 1-2-M are orthogonally demodulated after being frequency-converted in the receiving units 3-1-3-1-M connected to the antenna elements 1-1-1-1-M, and are reception signals composed of orthogonal I and Q signals. The signals are converted into 4-1 to 4-M and input to the main wave direction estimating unit 5.

A main wave direction estimating unit 5 for estimating the arrival direction of an incoming wave having the maximum power using the output signal 4 of the receiving unit 3
And an angle spread estimating unit 6 for estimating the angle spread in the direction of arrival of the arriving wave having the maximum power, and directing the directivity of the array antenna in the direction of arrival of the arriving wave having the maximum power.
Further, the operation of the weight generator 7 for generating an array weight whose beam width varies based on the estimation result of the angle spread estimator 6 is the same as that of the first embodiment, and the description thereof is omitted.

The modulator 20 modulates the input transmission data and modulates the baseband I signal I (k) and Q signal Q (k).
Generate The transmission beam forming unit 21 distributes the modulated baseband I signal I (k) and Q signal Q (k) in a number equal to the number M of array elements to be transmitted, and multiplies each by an array weight wm. (M =
1,. . . , M), that is, zm (k) = wm × (I (k) + jQ (k)) input signal to the m-th transmitting unit. However, m = 1 to M.

The transmission units 22-1 to 22-M convert the input baseband signal zm (k) into an RF transmission frequency and transmit the RF signal from each array element of the array antenna with a specified transmission power.

As described above, in the present embodiment, the direction of arrival of a radio wave is estimated from the signal received by array antenna 1, and
Further, it is possible to direct the main lobe in the direction of the arriving wave, and further transmit the beam in a directional pattern in which the beam width of the main lobe is varied according to the angular spread of the arriving wave. As a result, it is possible to sufficiently reduce interference with radio stations other than the radio station that is to perform communication, and when the angular spread is large, the temporal dispersion between rays constituting the angular spread is also large. Therefore, when the angular spread is larger than a predetermined value, the multipath suppression effect can be further enhanced by directing the directivity of the narrow beam from the main wave direction including those multipaths. The reception quality can be improved.

(Embodiment 4) FIG. 4 is a block diagram showing a configuration of an adaptive antenna apparatus. The operation will be described below with reference to FIG. M array antennas (where M>
It is composed of the antenna elements 1-1 to 1-M of 1). High-frequency signals received by the antenna elements 1-1 to 1-M 2-
The reception signals 1-2-M are orthogonally demodulated after being frequency-converted in the receiving units 3-1-3-1-M connected to the antenna elements 1-1-1-1-M, and are reception signals composed of orthogonal I and Q signals. The signals are converted into 4-1 to 4-M and input to the arrival direction estimation unit 10.

Output signals 4-1 to 4-1 of receiving sections 3-1 to 3-M
4-M, the arrival direction estimating unit 10 for estimating the arrival directions and the powers of a plurality of arrival waves, the maximum power wave among the plurality of arrival directions, and the arrival wave power within a predetermined value for the maximum power wave. And an angle spread estimating unit 11 for estimating an angle spread for the arriving wave, and in the case where the arriving wave whose incoming wave power is within a predetermined value with respect to the maximum power wave exists, The weight generator 12 for generating an array weight for directing the directivity of the array antenna in the direction of the maximum power wave is the same as in the second embodiment, and a description thereof will be omitted.

The transmitting beam forming section 21 modulates the transmitting data in the modulating section 20 with the modulated baseband I signal I
(K) and the Q signal Q (k) are distributed in a number equal to the number of array elements to be transmitted.
Multiply by That is, the input signal zm (k) to the m-th transmitting unit 22 becomes wm × (I (k) + jQ (k)). However, m = 1 to M.

The transmission units 22-1 to 22-M convert the input baseband signal zm (k) into an RF transmission frequency and transmit the RF signal from each array element of the array antenna with a specified transmission power.

As described above, in the present embodiment, the direction of arrival of a radio wave is estimated from the signal received by the array antenna, the main lobe is directed in the direction of the arrival wave, and the main lobe is further adjusted according to the angular spread of the arrival wave. It is possible to transmit with a directional pattern with a variable beam width. Thereby, it is possible to sufficiently reduce interference with radio stations existing other than the desired radio station to perform communication, and when there are a plurality of arriving waves, the reception power is relatively good, and ,
It is possible to select an arrival direction in which delay dispersion between rays constituting the angular spread is small, and to transmit in that direction, thereby improving reception quality at a desired wireless station.

(Embodiment 5) FIG. 5 is a block diagram showing a configuration of an adaptive antenna apparatus. The operation will be described below with reference to FIG. FIG. 5 shows the configuration of the adaptive antenna apparatus according to the first embodiment. In FIG. 1, the angle spread estimating unit 6 is eliminated and an interference wave arrival direction estimating unit 31 and an interference wave angle spread estimating unit 32 are added. It has a configuration,
An array weight for suppressing an interference wave is generated. Hereinafter, the different parts will be mainly described.

The operation until the received signal 4 is obtained by the array antenna 1 and the receiving section 3 is the same as that of the first embodiment. The main wave direction estimating unit 5 estimates the arrival direction of the incoming wave having the maximum power by using the output signal 4 from the receiving unit 3 by the operation in the first embodiment.

The interference wave arrival direction estimating unit 31 estimates the arrival direction of the interference wave using the output signal 4 of the receiving unit 3. Here, in the case of TDMA and FDMA, the interference wave is an incoming wave having a delay time that cannot be equalized by an equalizer in the succeeding demodulation unit 9 or an interference wave from another cell. , Assume users assigned to different codes. DS-C in IMT-2000
In the case of the DMA system, it is assumed that communication is performed in an environment in which a user performing high-speed data communication and a low-speed data communication or a voice user coexist. In particular, transmission power increases for a user performing high-speed data communication. The degree of interference with

The operation in the case where the present embodiment is applied as a CDMA base station will be described below. The interference wave arrival direction estimating unit 31 uses the received signal 4 to perform despreading using a code assigned to another user. Using a sampled signal for each of the I signal and the Q signal of the despread received signal, a complex digital signal expressed as a real part of the I signal and an imaginary part of the Q signal is a received signal h.
(T). Received signals h ₁ (k), h at sample times kΔT (where k is a natural number and ΔT is a sampling interval) obtained from the despread received signals, respectively.
₂ (k),. . . , H _M (k) to form a reception vector h (k) shown in (Equation 16), and further, using the reception vectors h (k) accumulated every predetermined N sample periods, a correlation matrix of (Equation 17) Find R _h . In this case, the correlation matrix R _h
Is an (M × M) matrix.

[0080]

(Equation 16)

[0081]

[Equation 17]

Next, the arrival angle is evaluated for each predetermined angle step Δφ using the arrival angle evaluation function based on the Capon method. The arrival angle evaluation function is represented by (Equation 18).

[0083]

(Equation 18)

Several maximum values are obtained in the angle spectrum as a result of the arrival angle evaluation. The maximum peak among them is the maximum power wave, and the angle at which the maximum peak is given is the interference wave direction φ ₀ .

Next, the operation of the interference wave angle spread estimating section 32 will be described below. The angular spread in the main wave direction φ ₀ obtained from the interference wave arrival direction estimating unit 31 is expressed by (Equation 19)
The angle spread parameter ψ is evaluated for each predetermined angle step Δψ using the angle spread evaluation function represented by

[0086]

[Equation 19]

With respect to the angle spread spectrum obtained by varying the angle spread parameter ψ in (Equation 19),
The angular spread value [psi ₀ giving the maximum peak to estimate.
Note that here, the angle spread is estimated using the generalized array mode vector for the Capon method.
The same applies to the case where the angle spread estimation is performed by applying the generalized array mode vector to the USIC method and the ESIPRIT method.

The weight generation section 30 directs the directivity of the array antenna in the arrival direction, and forms a null of directivity having a width corresponding to the spread of the interference wave in the interference wave direction when the arrival direction and the interference wave direction are not the same. To generate an array weight.
A DCMP method is typical as an array weight forming method when a desired wave direction and an interference wave direction are known. DCM
For details of the P method, see K. Takano, “An Adapt
live ArrayUnder Directiona
l Constraint ", IEEE Trans.
AP-24 (5), 1976. Constraint matrix C (number 20) array mode vector a (theta ₀₎ DOA theta ₀ as shown in, the array mode vector a (phi ₀₎ of the interference wave direction phi _0, further, the interference wave direction null width Array mode vector a (φ ₀ −α) in the vicinity of the interference wave direction corresponding to the angular spread in order to make it correspond to the angular spread of
ψ ₀ ) and a (φ ₀ + αψ ₀ ). Where α is a constant. The constraint response vector H is represented by (Equation 21). Here, T represents matrix transposition. The optimum weight Wopt obtained by the DCMP method is represented by (Equation 22). By using the array weight as Wopt, the directivity of the array antenna is oriented in the arrival direction, and when the arrival direction and the interference wave direction are not the same, a null of directivity having a width corresponding to the interference wave angle spread is formed in the interference wave direction. Array weight can be generated. By using (Formula 23) and (Formula 24) instead of (Formula 20) and (Formula 21) as the constraint matrix C and the constraint response vector H, the number of constraint conditions can be reduced from 4 to 3. When the number of array elements is small, it is possible to reduce the amount of calculation and to apply to the case where the number of array elements is small.

[0089]

(Equation 20)

[0090]

(Equation 21)

[0091]

(Equation 22)

[0092]

(Equation 23)

[0093]

(Equation 24)

By using the array weights obtained as described above for reception beam formation or transmission beam formation, it is possible to form a null width according to the angular spread of the interference wave, and to obtain an error in the arrival direction estimation. Is included, it is possible to improve the communication quality at the time of reception or transmission by forming a directivity having a high interference wave suppressing effect.

Note that the arrival direction estimating unit 10 and the angle spread estimating unit 11 explained in the second embodiment are used instead of the main wave direction estimating unit 5 in the present embodiment, When there are a plurality of arriving waves whose wave power is within a predetermined value, a configuration may be adopted in which the main beam is directed to the arrival direction of the arriving wave having the smallest angular spread among the arriving waves.

The third embodiment may use the interference wave arrival direction estimating unit 31 and the interference wave angle spread estimating unit 32 of the present embodiment, and the configuration in this case is as shown in FIG. The operations of the interference wave arrival direction estimating unit 31 and the interference wave angle spread estimating unit 32 are the same as those of the present embodiment, and the other operations are the same as those of the third embodiment. Is obtained. Also in this case, the arrival direction estimation unit 10 and the angle spread estimation unit 11 described in the fourth embodiment may be used instead of the main wave direction estimation unit 5.

(Embodiment 6) FIG. 7 is a block diagram showing another configuration of the adaptive antenna apparatus. In FIG. 7, the estimation result of the angle spread estimating unit 41 is fed back to the main wave direction estimating unit 40, and a function of switching the direction estimation algorithm in the main wave direction estimating unit 40 using this information is added. ing. Hereinafter, the operation of the main wave direction estimating unit 40, which is a different part, will be described with reference to the flowchart of FIG.

The operation until the received signal 4 is obtained by the array antenna 1 and the receiving section 3 is the same as that of the first embodiment (s70). Main wave direction estimator 4
0 first estimates the arrival direction of the received signal 4 by the first arrival direction estimation processing (s71). Here, the first direction-of-arrival estimation processing is a correlation matrix operation (s
71-1) After that, the arrival direction estimation evaluation function calculation (s71-2) shown in (Equation 3) or (Equation 12) is performed. The obtained arrival direction estimation result is input to the angle spread estimating unit 41 to obtain an angle spread estimated value (s72). The obtained angular spread value φ is compared with a predetermined value AS (s73), and φ
If ≤AS, the arrival direction estimation value at that time is used as the final estimation value (s74). On the other hand, when φ> AS,
A second direction-of-arrival estimation process is performed (s75). Here, in the second direction-of-arrival estimation processing, after the correlation matrix operation (s75-1) shown in (Equation 2), the obtained correlation matrix is further subjected to spatial smoothing processing using the number Ms of sub-array elements (s75). -2) Using the correlation matrix Rs obtained thereby, an arrival direction estimation evaluation function calculation represented by (Equation 3) or (Equation 12) is performed (s75-3). Where M
s ≦ M. The direction-of-arrival estimation value obtained in this way is used as the final estimation value (s74). For details on the spatial smoothing process, see the document Pilai et al, "Forward
/ Backward Spatial Smoothing Techniques for Coheren
t Signal Identification ", IEEE Trans. on Acoustic
s, speech and signal processing, VOL.37, NO.1, 198
9 mag.

As described above, in the present embodiment, it is possible to switch the direction-of-arrival estimation algorithm in main wave direction estimating section 40 depending on the magnitude of the angular spread. That is, when the angle spread is larger than the predetermined value, the arrival direction estimation algorithm in the main wave direction estimation unit 40 switches to an algorithm to which spatial smoothing processing is added. When the angle spread exceeds 10 degrees, the rays constituting the angle spread appear as multipaths with high correlation, so that the rank of the correlation matrix decreases and the incoming wave cannot be estimated with high accuracy. . Therefore, the estimation accuracy can be improved by performing the direction-of-arrival estimation processing to which spatial smoothing is added as shown in the present embodiment. Conversely, in a region where the angular spread is sufficiently small, it is possible to prevent deterioration in estimation accuracy due to a reduction in the array aperture surface due to the sub-array of the array antenna during the spatial smoothing process.

It should be noted that the direction-of-arrival estimation algorithm may be similarly switched according to the angular spread for the main-wave direction estimating unit described in the third embodiment of the present invention.

It is to be noted that the arrival direction estimating algorithm described in the second, fourth and fifth embodiments of the present invention may be similarly switched according to the angle spread.

It is to be noted that the direction-of-arrival estimation algorithm may be similarly switched in accordance with the angular spread for the direction-of-arrival-of-interference-wave estimating unit described in the fifth embodiment of the present invention.

[0103]

As described above, according to the present invention, the directivity of the array antenna at the time of reception or transmission is changed with respect to the position of the radio station in accordance with the arrival direction estimation and the angle spread estimation result.
The beam direction and beam width can be adaptively varied. Further, when an interference station exists, a null can be formed in the direction of the interference wave, and the null width can be changed according to the angular spread. Thus, by applying the present invention to a mobile communication base station that needs to communicate with a plurality of terminal stations, interference between terminals can be reduced, and communication quality and system capacity can be improved. it can.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an adaptive antenna device according to Embodiment 1 of the present invention.

FIG. 2 is a block diagram showing a configuration of an adaptive antenna device according to the second embodiment.

FIG. 3 is a block diagram showing a configuration of an adaptive antenna device according to the third embodiment.

FIG. 4 is a block diagram showing a configuration of an adaptive antenna device according to the fourth embodiment.

FIG. 5 is a block diagram showing a configuration of an adaptive antenna device according to the fifth embodiment.

FIG. 6 is a block diagram showing a configuration of an adaptive antenna device according to the fifth embodiment.

FIG. 7 is a block diagram showing a configuration of an adaptive antenna device according to the sixth embodiment.

FIG. 8 is a flowchart showing the operation of an arrival direction estimation processing unit according to the sixth embodiment.

FIG. 9 is a block diagram showing a configuration of a conventional adaptive antenna device.

[Explanation of symbols]

 Reference Signs List 1 array antenna 1-1 to 1-M antenna element 2-1 to 2-M high frequency signal 3-1 to 3-M receiving unit 4-1 to 4-M received signal 5 main wave direction estimating unit 6 angle spread estimating unit 7 weight generator 8 receive beamformer 9 demodulator

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Yasuaki Yuda 3-10-1, Higashi-Mita, Tama-ku, Kawasaki-shi, Kanagawa Prefecture Inside Matsushita Giken Co., Ltd. (72) Inventor Masayuki Hoshino 4-chome Tsunashima Higashi, Kohoku-ku, Yokohama-shi, Kanagawa No.3-1 F-term in Matsushita Communication Industrial Co., Ltd. (reference) 5J021 AA06 CA06 DB02 DB03 EA04 FA06 FA14 FA15 FA16 FA17 FA20 FA24 FA26 FA29 FA32 GA02 GA06 HA05 HA10 5K059 CC04 DD32

Claims (14)

[Claims] An array antenna including a plurality of antenna elements, a receiving unit that performs orthogonal detection after frequency conversion of a signal of an incoming wave received by each antenna element of the array antenna, and an output signal of the receiving unit. A main wave direction estimating unit for estimating an arrival direction of an incoming wave having a maximum power, and an angular spread estimating an angular spread in an arrival direction of the incoming wave having the maximum power using an output of the main wave direction estimating unit. An estimating unit, and a weight generating unit that directs the directivity of the array antenna in an arrival direction of the arriving wave having the maximum power, and further generates an array weight whose beam width varies based on the estimation result of the angle spread estimating unit. A receiving beam forming unit that multiplies the output signal of the receiving unit by the array weight and combines the received signal, and a demodulation unit that performs demodulation processing on the output signal of the receiving beam forming unit. An adaptive antenna device having a tuning unit. 2. An array antenna comprising a plurality of antenna elements, a receiving unit for performing quadrature detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna, and an output signal of the receiving unit. A direction-of-arrival estimating unit for estimating the directions of arrival and their powers of a plurality of arriving waves, and selecting a maximum power wave from the plurality of arriving waves by using an output of the direction-of-arrival estimating unit; Of which
An angle spread estimator for estimating an angle spread for an incoming wave whose power is within a predetermined value for the maximum power wave, and an incoming wave whose incoming wave power is within a predetermined value for the maximum power wave exists. A weight generation unit for generating an array weight for directing the directivity of the array antenna in the direction in which the angular spread is minimized, or in the case of the maximum power wave direction when not present, and multiplying the output signal of the reception unit by the array weight; An adaptive antenna device, comprising: a receiving beam forming unit for performing combining and demodulation; 3. An array antenna comprising a plurality of antenna elements, a receiving section for performing quadrature detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna, and an output signal of the receiving section. A main wave direction estimating unit for estimating an arrival direction of an incoming wave having a maximum power, and an angular spread estimating an angular spread in an arrival direction of the incoming wave having the maximum power using an output of the main wave direction estimating unit. An estimation unit, a weight generation unit that generates an array weight that directs the directivity of the array antenna in the arrival direction of the arriving wave having the maximum power, a transmission beam forming unit that multiplies a transmission signal by the array weight, A transmitting unit that transmits an output of a transmission beam forming unit from the array antenna. 4. An array antenna comprising a plurality of antenna elements, a receiving section for performing quadrature detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna, and an output signal of the receiving section. A direction-of-arrival estimating unit for estimating the directions of arrival and their power of a plurality of incoming waves using the output of the direction-of-arrival estimating unit to select a maximum power wave from the plurality of directions of arrival, Among them, there is an angle spread estimating unit for estimating an angle spread for an incoming wave whose power is within a predetermined value for the maximum power wave, and an incoming wave whose incoming wave power is within a predetermined value for the maximum power wave exists. In the case where the angular spread is minimized, when not present, in the direction of the maximum power wave, a weight generation unit that generates an array weight for directing the directivity of the array antenna, An adaptive antenna device comprising: a transmission beam forming unit that multiplies an array weight; and a transmitting unit that transmits an output of the transmission beam forming unit from the array antenna. 5. The adaptive antenna apparatus according to claim 2, wherein a beam width of the directivity formed by the weight generation unit is changed based on an estimation result of the angle spread estimation unit. 6. The adaptive antenna device according to claim 1, wherein the weight generating section forms a directional beam having a reduced beam width when the angular spread is larger than a predetermined value. 7. An array antenna composed of a plurality of antenna elements, a receiving section for performing quadrature detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna, and an output signal of the receiving section. A main wave direction estimating unit for estimating the direction of arrival of the arriving wave having the maximum power, an interference wave arrival direction estimating unit for estimating the direction of arrival of the interference wave using an output signal of the receiving unit, and An interference wave angle spread estimating unit for estimating an angular spread of the direction of arrival of the interference wave using an output of a direction estimating unit, and directing the directivity of the array antenna in the direction of arrival of the incoming wave having the maximum power; If the direction of the incoming wave having power and the direction of arrival of the interference wave are not the same, in the direction of arrival of the interference wave,
A weight generation unit that generates an array weight that forms a null of directivity having a width corresponding to the interference wave angle spread; a reception beam formation unit that multiplies an output signal of the reception unit by the array weight to synthesize the reception beam; An adaptive antenna device comprising: a demodulation unit that performs demodulation processing on an output signal of a formation unit. 8. An array antenna including a plurality of antenna elements, a receiving unit that performs quadrature detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna, and an output signal of the receiving unit. A direction-of-arrival estimating unit for estimating the directions of arrival and their powers of a plurality of arriving waves, and selecting a maximum power wave from the plurality of arriving waves by using an output of the direction-of-arrival estimating unit; Of which
An angle spread estimator for estimating an angle spread for an incoming wave whose power is within a predetermined value with respect to the maximum power wave, and an interference wave arrival direction estimating for estimating an arrival direction of the interference wave using an output signal of the receiver. An interference wave angle spread estimating unit for estimating an angular spread of the direction of arrival of the interference wave using an output of the interference wave arrival direction estimating unit; and an arrival wave whose arrival wave power is within a predetermined value with respect to the maximum power wave. When a wave is present, the direction of the array antenna is directed in the direction in which the angular spread is minimized, and when not present, in the direction of the maximum power wave, the direction in which the directivity of the array antenna is directed and the interference wave If the arrival directions of the interference waves are not the same, a weight generation unit that generates an array weight that forms a directional null having a width corresponding to the interference wave angle spread in the arrival direction of the interference wave, and an output signal of the reception unit. Adaptation has a receive beam forming unit for multiplying the rate weights synthesis, and a demodulation section that performs demodulation processing on the output signal of the receiving beam forming unit antenna device. 9. An array antenna including a plurality of antenna elements, a receiving unit that performs quadrature detection after frequency conversion of a signal of an incoming wave received by each antenna element of the array antenna, and an output signal of the receiving unit. A main wave direction estimator for estimating the direction of arrival of an incoming wave having the maximum power, an interference wave arrival direction estimator for estimating the direction of arrival of an interference wave using an output signal of the receiver, and the interference wave arrival direction. An interference wave angle spread estimating unit that estimates the angular spread of the direction of arrival of the interference wave using the output of the estimating unit, and directs the directivity of the array antenna to the direction of arrival of the incoming wave having the maximum power, and sets the maximum power. If the direction of the arriving wave and the direction of arrival of the interference wave are not the same, an array weight that forms a directional null having a width corresponding to the angle spread of the interference wave is generated in the direction of arrival of the interference wave. An adaptive antenna apparatus comprising: a weight generation unit; a transmission beam forming unit that multiplies a transmission signal by the array weight; and a transmission unit that transmits an output of the transmission beam forming unit from the array antenna. 10. An array antenna including a plurality of antenna elements, a receiving unit that performs quadrature detection after frequency conversion of an incoming wave signal received by each antenna element of the array antenna, and an output signal of the receiving unit. A direction-of-arrival estimating unit for estimating the directions of arrival and their powers of a plurality of arriving waves, and selecting a maximum power wave from the plurality of arriving waves by using an output of the direction-of-arrival estimating unit; Of which
An angle spread estimator for estimating an angle spread for an incoming wave whose power is within a predetermined value with respect to the maximum power wave, and an interference wave arrival direction estimating for estimating an arrival direction of the interference wave using an output signal of the receiver. An interference wave angle spread estimating unit for estimating an angular spread of the direction of arrival of the interference wave using an output of the interference wave arrival direction estimating unit; and an arrival wave whose arrival wave power is within a predetermined value with respect to the maximum power wave. When a wave is present, the direction of the array antenna is directed in the direction in which the angular spread is minimized, and when not present, in the direction of the maximum power wave, the direction in which the directivity of the array antenna is directed and the interference wave If the arrival directions of the interference waves are not the same, a weight generation unit that generates an array weight that forms a directional null having a width corresponding to the interference wave angle spread in the arrival direction of the interference wave; and Adaptive antenna device comprising a transmitting beamformer for multiplying the site, and a transmission unit for transmitting an output of the transmit beam forming unit from said array antenna. 11. According to the magnitude of the angular spread of the arriving wave,
The adaptive antenna device according to claim 1, 3 or 6, wherein the arrival direction estimation algorithm in the main wave direction estimation unit is switched. 12. According to the magnitude of the angular spread of the arriving wave,
The adaptive antenna device according to claim 2, 4, 5, 8, or 10, wherein a direction of arrival estimation algorithm in the direction of arrival estimation unit is switched. 13. According to the magnitude of the angular spread of the interference wave,
The adaptive antenna device according to claim 7, wherein an arrival direction estimation algorithm in the interference wave arrival direction estimation unit is switched. 14. The method according to claim 1, wherein when the angular spread is larger than a predetermined value, the arrival direction estimation algorithm is switched to an algorithm to which a spatial smoothing process is added.
14. The adaptive antenna device according to 1, 12, or 13.